JPH11159332A - Variable intake device for multicylinder engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multicylinder engine with independent intake manifold collectors for two-split cylinder groups and independent resonance pipes for the collectors, capable of increasing power in low and intermediate speed ranges with continuous resonance supercharge and in a high speed range with inertia supercharge. SOLUTION: A communication part 35 via which two resonance pipes 16A, 16B are communicated with each other is provided and a valve device 40 is provided therein. The valve device 40 constituting part of intake passage walls in the resonance pipes 16A, 16B has a first valve element 41 to expand an intake passage with opening operation and a collar second valve element 42 to open/close the communication part 35. With the continuous opening operation of the valve elements 41, 42, the intake passage is expanded to form the intake passage in harmony to a resonance supercharge point corresponding to the rotation of an engine and, with the further opening operation, the communication part 35 is opened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a variable intake device for a multi-cylinder engine.

[0002]

2. Description of the Related Art As a conventional variable intake device for an engine,
For example, there is one disclosed in JP-A-5-280352. This allows a main passage and a sub passage provided in the intake passage of the engine, a butterfly-type control valve that opens the main passage at a high speed and closes at a low / middle speed, and allows a flow in a suction direction of the sub passage. A check valve that is closed by a flow in the opposite direction.

[0003] According to this, when the engine is running at a high speed, a large amount of intake air is supplied with a small passage resistance by opening a control valve, thereby improving the charging efficiency of the intake air.
By closing the control valve at the time of medium rotation, the flow rate of the intake air can be increased, and the charging efficiency of the intake air can be improved.

[0004]

However, in such a conventional variable intake system for an engine, the output from the check valve is large at low / medium rotation speed and the flow direction is not smooth. When the engine speed is high, the output is reduced due to the resistance of the valve shaft of the control valve and the resistance of the check valve at the time of high rotation, so that the output cannot be increased as desired.

The present invention has been made in view of the above-mentioned conventional problems, and a multi-cylinder engine provided with an independent intake manifold collector and an independent resonance pipe for each collector in each of two divided cylinder groups. It is an object of the present invention to significantly improve output performance by continuous resonance supercharging in a low / medium rotation region and by inertia supercharging and reduction of ventilation resistance in a high rotation region.

[0006]

For this reason, in the invention according to claim 1, each of the two divided cylinder groups is provided with an independent intake manifold collector section and an independent resonance pipe to each collector section. In a multi-cylinder engine,
A first valve body that forms a part of an intake passage wall in each of the resonance pipes and that can expand the intake passage by a valve opening operation; and a second valve body that can open and close a communication part that communicates the two resonance pipes. Then, by the continuous valve opening operation of these valve bodies, the intake passage is expanded in a state where the communication portion is closed to obtain an intake passage shape synchronized with a resonance supercharging point corresponding to the engine rotation, and further opened. A variable intake device for a multi-cylinder engine is provided by providing a valve device for opening the communication portion by a valve operation.

[0007] In the invention according to claim 2, the two resonance tubes are formed by defining one duct by a partition wall extending from one inner surface to the center, and the two ducts are provided with a protruding end of the partition wall. A communication part is formed between the other inner surface. The first valve body extends in the communication portion along the other inner surface, and is operable to change a distance from the other inner surface. It is characterized by projecting from the first valve body so as to be orthogonal to the first valve body.

According to a third aspect of the present invention, the first valve body has a fulcrum relatively upstream of the resonance tube and swings on the downstream side. The invention according to claim 4 is characterized in that a flap for closing a space on the back side of the first valve body is provided at a downstream end of the first valve body. The invention according to claim 5 is characterized in that the flap is provided so as to be relatively displaceable with respect to the first valve body.

The invention according to claim 6 is characterized in that the flap is provided integrally with the first valve body. In the invention according to claim 7, for the valve device,
A control device is provided that allows the valve opening operation to be performed continuously from the low engine speed region to the middle engine speed region, and further performs the valve opening operation in the high engine speed region.

[0010]

According to the first aspect of the present invention, a continuous valve opening operation of the valve device expands the intake passage in a state where the communication portion of the two resonance pipes is closed, and resonates according to the engine rotation. By obtaining an intake passage shape that is synchronized with the supercharging point, the resonance supercharging effect can be sufficiently exerted over the entire range of low and medium speeds, and the output performance can be improved.
By opening the communication part of the two resonance tubes to make it equivalent to one collector, it is possible to obtain an effect that switching to inertial supercharging and a large increase in high-speed output can be achieved.

According to the second aspect of the present invention, with a relatively simple configuration, control can be performed by a single valve device having the first valve body and the second valve body integrally, and an increase in cost can be suppressed.
According to the third aspect of the invention, the downstream side of the resonance tube can be expanded, the flow of intake air can be made smooth, the ventilation resistance can be significantly reduced, and the output can be increased. According to the fourth aspect of the invention, since the flap for closing the space on the back side of the first valve body is provided, it is possible to avoid an increase in the intake volume when the valve device is in a closed state. Responsiveness of the engine and the engine stall when the idling speed is reduced can be prevented.

According to the fifth aspect of the present invention, by providing the flap so as to be relatively displaceable with respect to the first valve body, it becomes possible to appropriately control the intake volume at the time of the valve opening operation of the valve device.
According to the invention of claim 6, by providing the flap integrally with the first valve body, the configuration of the valve device can be simplified. According to the invention according to claim 7, the valve opening operation is continuously performed from the low engine speed region to the medium engine speed region, and the further valve opening operation is performed in the high engine speed region, so that the low / medium speed is achieved. And the high-speed output can be reliably achieved.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic front view of a V-type six-cylinder engine to which the present invention is applied, and FIG. 2 is a schematic plan view of the same. In the figure, 10 is a cylinder block, 11A and 11B are cylinder heads, 12A and 12B are rocker covers,
It is divided into a bank on the first cylinder group side composed of # 1, # 3, and # 5 cylinders and a bank on the second cylinder group side composed of # 2, # 4, and # 6 cylinders.

The rocker cover 12 of one bank
Above A, an intake manifold 13 is arranged.
The intake manifold 13 has a total of six branch pipes 14-1 to 14-6 extending three to each bank, and each of the branch pipes 14-1 to 14-1.
4-6 has a collector (surge tank) 15 to which an upstream end is collectively connected.

The collector section 15 includes a resonance tube 16.
Through the throttle chamber (throttle body) 17
Is installed. The throttle chamber 17 and its upstream side are omitted in FIG. 1 and are shown only in FIG. The throttle chamber 17 has a throttle valve therein and has an idle control valve 1 for controlling an idle speed in a bypass passage that bypasses the throttle valve.
Eight.

The upstream side of the throttle chamber 17 is connected to a clean side of an air cleaner 21 via an intake duct 19 and an air flow meter 20, and an outside air introduction duct 22 is provided on the dust side. next,
The portions of the intake manifold collector 15 and the resonance tube 16 will be described in more detail.

FIG. 3 is a schematic front view of an intake system schematically shown.
FIG. 4 is a schematic plan view of the intake system in a fully closed state,
5 is a schematic plan view of the intake system with the valve device half-opened, FIG. 6 is a schematic plan view of the intake system with the valve device fully opened, and FIGS.
8 is a cross-sectional view taken along the line AA ′ of FIGS. 4 to 6, FIG. 8 is a schematic perspective view showing the shape of the valve body of the valve device, FIG. 9 is a schematic plan view showing the shape of the valve body of the valve device, and FIG. It is a schematic diagram.

The intake manifold / collector unit 15 is divided into upper and lower parts by a partition wall 31, and is provided with first and second collector parts 15A and 15B which are independent of each of the two divided cylinder groups. That is, the upper side is the first
Of the cylinder group (# 1, # 3, # 5 cylinder)
-1, 14-3, 14-5, the first collector portion 15 connected to
A, and the lower side is the second cylinder group (# 2, # 4, #
The second collector portion 15B is connected to the branch pipes 14-2, 14-4, and 14-6 on the (six cylinders) side.

The resonance tube 16 is divided into upper and lower parts by a partition wall 33, and each of the first and second collector parts 15A, 15A
B independent first and second resonance tubes 16A and 16B. That is, the upper side forms the first resonance tube 16A connected to the first collector section 15A, and the lower side forms the second collector section 1A.
A second resonance tube 16B connected to 5B is formed. here,
The first and second resonance tubes 16A and 16B are formed by defining one duct by a partition wall 33 extending from one inner surface 32 to the center, and the protruding end of the partition wall 33 and the other end are formed. A communication portion 35 is formed between the inner surface 34 and the inner surface 34 (see FIG. 7). The first and second resonance tubes 16
In A and 16B, the downstream side passage is expanded by positioning the other inner side surface 34 to the outside as it goes downstream.

The communication unit 35 is provided with a valve device 40. The valve body of the valve device 40 is
A first valve body 41 which forms a part of the intake passage wall in A and 16B and can expand the intake passage by a valve opening operation, and a second valve which can open and close a communication portion 35 communicating the two resonance pipes 16A and 16B.
The first valve body 41 has a flap 43 on the distal end side (see FIGS. 8 and 9).

Here, the first valve body 41 has a curved plate shape, extends along the other inner side surface 34 in the communication portion 35, and changes the distance from the other inner side surface 34. Operable. Specifically, the first valve body 41 is
With a fulcrum 41a relatively upstream of the resonance tubes 16A and 16B, the downstream end 41b swings from the position of FIG. 4 to the position of FIG. 6 via the position of FIG. Also, the first valve body 41
At the upper and lower edges of are provided flange-shaped guide portions 41c and 41d along the top and bottom surfaces of the resonance tubes 16A and 16B (see FIG. 7).

The second valve body 42 protrudes from the center of the plate surface of the first valve body 41 in a flange shape so as to be orthogonal to the plate surface.
From the position (of FIG. 7) to the position of FIG. 5 (of FIG. 7), the communication portion 35 is closed within the slit 36 provided in the partition wall 33, and the position shown in FIG. When it moves from the position to the position shown in FIG. 6 (FIG. 7), it goes out of the slit 36 and opens the communication portion 35. The hatched part in FIG. 6 shows the communicating part 35 that is opened.

The flap 43 is connected to the downstream end 4 of the first valve body 41.
The first valve body 41 is swingably attached to the first valve body 41 so as to close the downstream side of the space behind the first valve body 41. The first valve element 41 is driven by a step motor or a DC motor 44 provided at a fulcrum 41a.
The operation of 4 is controlled by a control device (control unit) 45 (see FIG. 10). Instead of driving using the motor 44, it is also possible to perform multi-stage control using a negative pressure diaphragm or the like. The flap 43 is driven by a linkage (not shown) as the first valve body 41 rotates.

Next, the operation will be described. The control device 45 uses the engine speed calculated based on the signal from the crank angle sensor and the engine load obtained by dividing the intake air amount detected by the air flow meter by the engine speed as operating condition parameters, As shown in FIG. 11, the opening of the valve device 40 is controlled as follows with reference to a map to which the opening of the valve device 40 is assigned.

Low rotation range (for example, 2000 rpm or less)
Then, the valve device 40 is brought to the fully closed state shown in FIG. 4 (FIG. 7). At this time, the downstream end 41b of the first valve body 41 protrudes into the intake passage, narrows the intake passage, and synchronizes with the resonance supercharging point at a low rotation speed (the sectional area of the pipe × length).
Get.

From the low rotation / low load region to the middle rotation /
Up to the middle load region, the valve device 40 is moved from the position of FIG. 4 (of FIG. 7) to the position of FIG.
The opening is continuously controlled up to the position of). At this time, the downstream end 41b of the first valve body 41 retreats from the center side of the intake passage and expands the intake passage.

As a result, the resonance supercharging point moves to the high rotation side. Therefore, the opening is adjusted from low rotation to high rotation so as to have a pipe sectional area × length synchronized with the resonance supercharging point according to the engine rotation. Therefore, the resonance supercharging effect can be sufficiently exhibited in all the low and medium speed ranges, and the output performance can be improved.

On the other hand, in the high rotation / high load range, the valve device 4
0 is turned ON / OFF at once from the position shown in FIG. 5 (FIG. 7) to the position shown in FIG. At this time, the downstream end 41b of the first valve element 41 is most retracted, and not only is the air path expanded the most, but also the second valve element 42 comes out of the slit 36 of the partition wall 33 and the communication section 3
5 is opened. That is, the hatched portion in FIG. 6 is opened.

As a result, the intake air charging efficiency becomes equivalent to one collector, and the intake charging efficiency can be improved by the inertia supercharging effect. Also, the ventilation resistance is greatly reduced. Therefore, the high-speed output can be increased. The flap 43 closes the space on the back side of the first valve body 41 on the downstream side, secures sealing performance, and avoids an increase in intake volume. That is, although the intake volume increases by the amount that the other inner side surface 34 is positioned outside in advance, when the intake volume increases, intake responsiveness deteriorates, and engine stall occurs when idling speed is reduced. Therefore, the space on the back side of the first valve body 41 is securely closed to prevent such an adverse effect.

FIG. 12 shows the effect of the present invention.
In the figure, A is a basic characteristic of the output with respect to the engine speed. If the output is increased at a low speed and the output is increased at a high speed as in the conventional example, it can be improved as shown in A1 and A2. , The effect is not so great. On the other hand, in the present invention, low rotation (for example, 2000 rpm)
m), the medium rotation (for example, 4000 to
Until the resonance supercharging effect at 5000 rpm), the resonance supercharging effect according to the engine rotation can be continuously exerted to increase the output, and the inertia supercharging effect and the ventilation can be achieved as in the high rotation speed region. By reducing the resistance, the output can be increased, and a large output can be obtained over the entire area.

Next, another embodiment of the present invention will be described. 13 is a schematic plan view of another embodiment of the present invention in a fully opened state of the intake system valve device, FIG. 14 is a schematic plan view of the intake system valve device in a half open state, and FIG. 15 is a fully opened intake system valve device. 16 is a schematic perspective view showing the shape of the valve element of the valve device, and FIG. 17 is a schematic plan view showing the shape of the valve element of the valve device. 13 to 15 are the same as those in FIGS.

In this embodiment, the flap 43 is provided integrally with the downstream end 41b of the first valve body 41, and forms an escape space 50 for allowing the flap 43 to escape when the valve is opened. Therefore, the valve device 40 and its driving mechanism can be simplified. Next, another embodiment of the present invention applied to an in-line six-cylinder engine will be described. FIG. 18 is a schematic plan view of an intake system in the case of an in-line six-cylinder engine, and FIG. 19 is a schematic front view of the intake system.

In this embodiment, the intake manifold collector 15 is divided into two parts in the front-rear direction of the engine by a partition wall 31, and the first and second collector parts 15A, 15A, which are independent of each of the two divided cylinder groups. 15B. That is, one is in the first cylinder group (#
1, # 2, # 3 cylinder) side branch pipes 14-1, 14-2, 1
4-3 constitutes a first collector portion 15A, and the other is a branch pipe 1 on the second cylinder group (# 4, # 5, # 6 cylinder) side.
Second collector unit 1 connected to 4-4, 14-5, and 14-6
5B.

The resonance tube 16 is divided into two parts in the front-rear direction of the engine by a partition wall 33, and independent first and second resonance tubes 16 are respectively connected to the first and second collector portions 15A and 15B.
A, 16B. That is, one forms a first resonance tube 16A connected to the first collector unit 15A, and the other forms a second resonance tube 16B connected to the second collector unit 15B.

Here, the first and second resonance tubes 16A, 16
B is formed by defining one duct by a partition wall 33 extending from one inner surface (top surface) to the center of the duct, and has a protruding end of the partition wall 33 and the other inner surface (bottom surface). A communication portion 35 is formed between the two. Further, a valve device 40 is provided in the communication portion 35. The structure of the valve device 40 is the same as that of the above-described embodiment except that the direction is different.

With this configuration, substantially the same effects as those of the above-described embodiment can be obtained in the in-line six-cylinder engine.

[Brief description of the drawings]

FIG. 1 is a schematic front view of a V-6 engine showing one embodiment of the present invention.

FIG. 2 is a schematic plan view of the above.

FIG. 3 is a schematic front view of a schematic intake system.

FIG. 4 is a schematic plan view of the intake system when the valve device is fully closed.

FIG. 5 is a schematic plan view of the intake system in a half-opened state;

FIG. 6 is a schematic plan view of the intake system with the valve device fully opened.

FIG. 7 is a sectional view taken along line A-A ′ of FIGS. 4 to 6;

FIG. 8 is a schematic perspective view showing a valve body shape of the valve device.

FIG. 9 is a schematic plan view showing a valve body shape of the valve device.

FIG. 10 is a schematic diagram of a control system.

FIG. 11 is a diagram showing a map for controlling the opening of the valve device.

FIG. 12 is a diagram showing the effect of the present invention.

FIG. 13 is a schematic plan view showing another embodiment of the present invention in a fully closed state of a valve device of an intake system.

FIG. 14 is a schematic plan view of the intake system valve device in a half-open state.

FIG. 15 is a schematic plan view of the intake system with the valve device fully opened.

FIG. 16 is a schematic perspective view showing a valve body shape of the valve device.

FIG. 17 is a schematic plan view showing a valve body shape of the valve device.

FIG. 18 is a schematic plan view of an intake system showing another embodiment of the present invention applied to an in-line six-cylinder engine.

FIG. 19 is a schematic front view of an intake system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Cylinder block 11A, 11B Cylinder head 12A, 12B Rocker cover 13 Intake manifold 14-1 to 14-6 Branch pipe 15, 15A, 15B Collector part 16, 16A, 16B Resonance pipe 17 Throttle chamber 18 Idle control valve 19 Intake duct 20 Air flow meter 21 air cleaner 22 outside air introduction duct 31 partition wall 32 one inner surface 33 partition wall 34 the other inner surface 35 communication part 36 slit 40 valve device 41 first valve body 41a fulcrum 41b downstream end 41c, 41d guide part 42 second Valve 43 Flap 44 Motor 45 Controller 50 Escape space

Claims (7)

[Claims] 1. A multi-cylinder engine having an independent intake manifold collector section and an independent resonance pipe to each collector section in each of two divided cylinder groups, wherein each of the resonance pipes has one intake passage wall. And a second valve body that can open and close a communication part that communicates the two resonance pipes with a first valve body that constitutes a part and expands an intake passage by a valve opening operation. By the valve opening operation, the intake passage is expanded in a state where the communication portion is closed to obtain an intake passage shape synchronized with the resonance supercharging point according to the engine rotation, and the communication portion is opened by the further valve opening operation. A variable intake device for a multi-cylinder engine, comprising a valve device. 2. The two resonance tubes are formed by defining one duct by a partition wall extending from one inner surface to the center, and forming a duct between a protruding end of the partition wall and the other inner surface. A communication portion is formed therebetween, wherein the first valve body extends along the other inner surface in the communication portion, and is operable to change a distance from the other inner surface, The variable intake device for a multi-cylinder engine according to claim 1, wherein the second valve body projects from the first valve body so as to be orthogonal to the first valve body. 3. The variable intake system for a multi-cylinder engine according to claim 2, wherein the first valve element has a fulcrum relatively upstream of the resonance pipe and swings downstream. . 4. A variable intake device for a multi-cylinder engine according to claim 3, further comprising a flap at a downstream end of said first valve body for closing a space on a rear side of said first valve body. 5. The variable intake device for a multi-cylinder engine according to claim 4, wherein said flap is provided so as to be displaceable relative to said first valve body. 6. The variable intake device for a multi-cylinder engine according to claim 4, wherein said flap is provided integrally with said first valve body. 7. A control device is provided for causing the valve device to continuously open a valve from a low engine speed region to a middle engine speed region and further perform a valve opening operation in a high engine speed region. The variable intake device for a multi-cylinder engine according to any one of claims 1 to 6, characterized in that: